Fructose-6-phosphate (F6P) is an important intermediate in the glycolytic pathway which leads from glucose to pyruvate. It is formed from glucose-6-phosphate and is further phosphorylated to fructose-1,6-diphosphate which is subsequently cleaved to glyceraldehyde phosphate and dihydroxyacetone phosphate. The transformation of glucose-6-phosphate is controlled by phosphoglucose isomerase, a very interesting enzyme in that it possesses multiple functions, as an isomerase, a neuroleukin, an autocrine motility factor and a differentiation and maturation mediator (1). BioVision's PicoProbe ™ Fructose-6-phosphate Assay Kit is a fluorescence-based simple, highly sensitive and rapid means of quantifying F6P in a variety of samples. In the assay, F6P is converted to glucose-6-phosphate which is subsequently oxidized with the generation of a fluorescent product. The PicoProbe™ F6P Assay Kit can detect F6P in the range of 0.01 to 0.5 nmoles with detection sensitivity ~1 µM of F6P.